1. Field of the Invention
This invention relates to fastening elements and fasteners and, more particularly, to these fastening elements which are used in conjunction with a mandrel and which are insertable into preformed holes.
2. Description of the Prior Art
Such fastening elements are used in the prior art as expanding mandrels to be inserted in masonry holes, as, for example, are disclosed in German Utility Model Specification No. 78 14 794 for fastening elements to a plate. These elements suffer from the disadvantage that they are only capable of withstanding shear stresses to a limited extent.